Explore topic-wise MCQs in Digital Electronics.

This section includes 35 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

Assembly language is written using mnemonics: MVI, DCR, JZ.

A. 1
B.
Answer» B.
2.

Conversion from assembly language to machine language can be done by the programmer through a process called hand assembly.

A. 1
B.
Answer» B.
3.

The 8085 software is compatible with the 8080A.

A. 1
B.
Answer» B.
4.

LDA addr and STA addr are Fortran language instructions stored in an external memory IC for a microprocessor.

A. 1
B.
Answer» C.
5.

A microprocessor with the necessary support circuits will include at least two memory ICs: ROM or EPROM, and a RAM.

A. 1
B.
Answer» B.
6.

What kind of computer program is used to convert mnemonic code to machine code?

A. debug
B. assembler
C. C++
D. Fortran
Answer» C. C++
7.

Single-bit indicators that may be set or cleared to show the results of logical or arithmetic operations are the:

A. flags
B. registers
C. monitors
D. decisions
Answer» B. registers
8.

Which of the following are the three basic sections of a microprocessor unit?

A. operand, register, and arithmetic/logic unit (ALU)
B. control and timing, register, and arithmetic/logic unit (ALU)
C. control and timing, register, and memory
D. arithmetic/logic unit (ALU), memory, and input/output
Answer» C. control and timing, register, and memory
9.

Because microprocessor CPUs do not understand mnemonics as they are, they have to be converted to ________.

A. hexadecimal machine code
B. binary machine code
C. assembly language
D. all of the above
Answer» C. assembly language
10.

The items that you can physically touch in a computer system are called:

A. software
B. firmware
C. hardware
D. none of the above
Answer» D. none of the above
11.

The software used to drive a microprocessor-based system is called FORTRAN.

A. 1
B.
C. 1
D.
Answer» C. 1
12.

The technique of assigning a memory address to each I/O device in the computer system is called:

A. memory-mapped I/O
B. ported I/O
C. dedicated I/O
D. wired I/O
Answer» B. ported I/O
13.

The 8085A is a(n):

A. 16-bit parallel CPU
B. 8-bit serial CPU
C. 8-bit parallel CPU
D. none of the above
Answer» D. none of the above
14.

Which of the following buses is primarily used to carry signals that direct other ICs to find out what type of operation is being performed?

A. data bus
B. control bus
C. address bus
D. address decoder bus
Answer» C. address bus
15.

A register in the microprocessor that keeps track of the answer or results of any arithmetic or logic operation is the:

A. stack pointer
B. program counter
C. instruction pointer
D. accumulator
Answer» E.
16.

Programs written for the 8080A must have slight modifications to run on the 8085A.

A. 1
B.
Answer» C.
17.

What type of circuit is used at the interface point of an output port?

A. decoder
B. latch
C. tristate buffer
D. none of the above
Answer» C. tristate buffer
18.

Which bus is a bidirectional bus?

A. address bus
B. data bus
C. address bus and data bus
D. none of the above
Answer» C. address bus and data bus
19.

I/O-mapped systems identify their input and output devices by giving them an 8-bit port number.

A. 1
B.
Answer» B.
20.

I/O mapped systems identify their input/output devices by giving them a(n) ________.

A. 8-bit port number
B. 16-bit port number
C. 8-bit buffer number
D. 8-bit instruction
Answer» B. 16-bit port number
21.

What type of circuit is used at the interface point of an input port?

A. decoder
B. latch
C. tristate buffer
D. none of the above
Answer» D. none of the above
22.

When referring to instruction words, a mnemonic is:

A. a short abbreviation for the operand address
B. a short abbreviation for the operation to be performed
C. a short abbreviation for the data word stored at the operand address
D. shorthand for machine language
Answer» C. a short abbreviation for the data word stored at the operand address
23.

A microcontroller integrates multichip systems with RAM, ROM, and I/O.

A. 1
B.
Answer» B.
24.

All computer programs for a machine are called:

A. software
B. firmware
C. hardware
D. none of the above
Answer» B. firmware
25.

The register in the 8085A that is used to keep track of the memory address of the next op-code to be run in the program is the:

A. stack pointer
B. program counter
C. instruction pointer
D. accumulator
Answer» C. instruction pointer
26.

What is the difference between a mnemonic code and machine code?

A. There is no difference.
B. Machine codes are in binary, mnemonic codes are in shorthand English.
C. Machine codes are in shorthand English, mnemonic codes are in binary.
D. address bus
Answer» C. Machine codes are in shorthand English, mnemonic codes are in binary.
27.

The software used to drive microprocessor-based systems is called:

A. assembly language
B. firmware
C. machine language code
D. BASIC interpreter instructions
Answer» B. firmware
28.

The ________ ensures that only one IC is active at a time to avoid a bus conflict caused by two ICs writing different data to the same bus.

A. control bus
B. control instructions
C. address decoder
D. CPU
Answer» D. CPU
29.

The control bus and memories share a bidirectional bus in a typical microprocessor system.

A. 1
B.
C. software
D. firmware
Answer» C. software
30.

When was the first 8-bit microprocessor introduced?

A. 1969
B. 1974
C. 1979
D. 1985
Answer» C. 1979
31.

The stack is a data storage area in RAM used by certain microprocessor operations.

A. 1
B.
C. 1
D.
Answer» B.
32.

The circuits in the 8085A that provide the arithmetic and logic functions are called the:

A. CPU
B. ALU
C. I/O
D. none of the above
Answer» C. I/O
33.

How many buses are connected as part of the 8085A microprocessor?

A. 2
B. 3
C. 5
D. 8
Answer» C. 5
34.

How many bits are used in the data bus?

A. 7
B. 8
C. 9
D. 16
Answer» C. 9
35.

The devices that provide the means for a computer to communicate with the user or other computers are referred to as:

A. CPU
B. ALU
C. I/O
D. none of the above
Answer» D. none of the above